parse.y: fail if yyerror

* parse.y (assignable_gen): fail if yyerror occurred.  fix a bug in
  r36973.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37251 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Thu Oct 18 10:30:34 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* parse.y (assignable_gen): fail if yyerror occurred.  fix a bug in
+	  r36973.
+
 Thu Oct 18 09:23:03 2012  Aaron Patterson <aaron@tenderlovemaking.com>
 
 	* hash.c (initialize_copy): duping should rehash the hash.

parse.y

@@ -8468,25 +8468,25 @@ assignable_gen(struct parser_params *parser, ID id, NODE *val)
     switch (id) {
       case keyword_self:
 	yyerror("Can't change the value of self");
-	break;
+	goto error;
       case keyword_nil:
 	yyerror("Can't assign to nil");
-	break;
+	goto error;
       case keyword_true:
 	yyerror("Can't assign to true");
-	break;
+	goto error;
       case keyword_false:
 	yyerror("Can't assign to false");
-	break;
+	goto error;
       case keyword__FILE__:
 	yyerror("Can't assign to __FILE__");
-	break;
+	goto error;
       case keyword__LINE__:
 	yyerror("Can't assign to __LINE__");
-	break;
+	goto error;
       case keyword__ENCODING__:
 	yyerror("Can't assign to __ENCODING__");
-	break;
+	goto error;
     }
     switch (id_type(id)) {
       case ID_LOCAL:
@@ -8526,6 +8526,7 @@ assignable_gen(struct parser_params *parser, ID id, NODE *val)
       default:
 	compile_error(PARSER_ARG "identifier %s is not valid to set", rb_id2name(id));
     }
+  error:
     return assignable_result(0);
 #undef assignable_result
 #undef parser_yyerror

test/ruby/test_syntax.rb

@@ -187,8 +187,10 @@ class TestSyntax < Test::Unit::TestCase
   end
 
   def test_unassignable
+    gvar = global_variables
     %w[self nil true false __FILE__ __LINE__ __ENCODING__].each do |kwd|
       assert_raise(SyntaxError) {eval("#{kwd} = nil")}
+      assert_equal(gvar, global_variables)
     end
   end